Millenials have been moving away from organized religion, but lately we seem to want some of it back. There is a rising swath of "organizations [that] use secular language while mirroring many of the functions fulfilled by religious community," such as community, personal transformation, and purpose-finding. These spaces range from SoulCycle to Camp Grounded to The Dinner Party.

So what makes sacred spaces truly "sacred"? Can historically sacred spaces be replicated in a different, secular context? I venture to one of the world's most sacred cities - Jerusalem - to find out.

The Church of the Holy Sepulchre: Old City, Jerusalem.

As I watch a long line of Orthodox women bow, touch, wipe and kiss a single slab of stone repeatedly, I admittedly think to myself: "Isn't all this touching and kissing a bit much? Fine, I get that this is the stone that Jesus' dead body laid on, but I am a Protestant child of postmodernism, after all, so how am I supposed to trust that this is really the stone that Jesus died on just because a lot of old people have said so?"

I visit the prison where Jesus was supposedly kept, and I have a similar reaction: "The bright, cheery flowers strewn all over make this prison look too gaudy and touristy." You see, I hail from NYC where "authentic" looks like untouched wood and decrepit brick, and where we jeer at happy tourists.

While a couple next to me bends down to place their candles, I look around, try to decide if it is OK with Jesus if I take a picture of his prison, and then leave. As I am walking in the small hallway, an elderly woman, robed in black, suddenly stumbles out a few feet in front of me. She finds a place to bow and starts weeping her eyes out in a foreign language. And it hits me that the truth is if I actually let the weight of what I was witnessing sink in, I would probably be kneeling next to her crying too.

Instead I take a photo of her, my fumbling attempt to pay some sort of homage to her. To remind me that what makes this ancient city sacred is not its stones, but its people.

So what if that stone is not really the resurrection stone, or that hole in the rock not the actual prison of Jesus? The fact is that people believe it to be so. And so it is their devotion that sanctifies these sites. That prison might be gaudy, but that is because it is, above all, a shrine. And when I think of it as a shrine, then all the gaudiness makes sense. This is where the sacredness of the Old City, to me, is found: Not in its historical stones, but in the layers of tears, skin, saliva, wax and petals that are piling up on top of them. It is the living Church, rooted in history and place, that is the true diadem of beauty.

A few months later, I am back in NYC, seated around a table on a roof, with a nice view of the Manhattan skyline. Its a luxurious building in the Upper West Side, but it oddly feels like Jerusalem.

There are five other women, all of whom are basically strangers to me. I have started going to this particular "house church" or "small group," as part of All Angels Church, where we gather to discuss Scripture, share our lives, and pray for one another. The discussion prompt today is "describe a time in which you felt extremely vulnerable." There is an initial silence, but soon woman after woman starts sharing some of the darkest moments of their lives, and their relationship with God through it all. We sit with each story, trying to acknowledge the weight of what was just shared. close with prayer at the end.

The sacred poignancy of those few hours on the roof was not quite about the text we are reading or the environment in which we were. It was more about the fact that we all implicitly agreed to demarcate this space as holy: a place in which we step away from fear and into truth, from suspicion into trust, from fragmented isolation into a whole interdependence.

It would be too far a leap, though, to think that the sacredness was solely due to human projection and effort, and that one could easily recreate a similar experience in a secular context. It is not that the church has a monopoly on vulnerability--that ingredient can exist within any tight-knit group. But that is it, in a way. Nobody vetted me before disclosing their story; I was a stranger to them. It was an instantaneous thing; I stepped off the strutting streets of Manhattan and immediately entered into a safe bed of secrets. Of course, there are support groups of all kinds, but never a support group for life, just for living with the craziness of our normal lives.

Now, not all church small groups are like this one; they take work, effort and leadership to create. But there is something about sharing a common confession that we are all in need of a salvation outside of ourselves, as we journey together towards a better version of ourselves, that seems fundamental to this whole experience. This shared confession and commitment was at the heart of our devotion there on that roof, the same devotion that drove the Orthodox women mad in front of Jesus' tombstone. They too were pouring out their hearts, searching for some salvific blessing. And so our devotion sanctifies both a roof and a stone.

So what ought the public witness of the Church look like in the 21st century? Whatever it is, it has to start with, and be sustained in, nothing less than a private circle of devotion.

"... just as I have loved you, you also are to love one another. By this all people will know that you are my disciples, if you have love for one another."

Sarah Ngu (@sarahngu) is a freelance writer and an alumni of Trinity Forum Academy and Columbia University. Based in New York, she writes regularly here and elsewhere on faith and culture, and produces thought leadership for businesses.